The phrase is a favourite of the alt-right movement, and has been supported by Ku Klux Klan grand wizard David Duke and other white nationalists.

On Tuesday, government Senate leader Mathias Cormann -- who did not vote in Monday's motion -- was forced into the embarrassing claim that the government did not actually support the motion, but that they were confused about what they were voting for.

"As a result of an administrative process failure, the government senators in the chamber ended up on advice voting in support of the motion. As leader of the government in the Senate, I take responsibility for that error and I'm sorry that that happened," Cormann said.

"It is indeed regrettable... it slipped through. It shouldn't have."

Hanson's motion had been originally raised several weeks ago and had been on the Senate notice paper for some time.

In August Anning made headlines when he invoked the phrase "final solution" -- a term used by the Nazi regime to describe its extermination of Jewish people -- during his highly controversial maiden speech to parliament in August.

Attorney-General Christian Porter -- who sits in the lower house and therefore did not vote in Monday's Senate motion, but who tweeted his support of it on Monday night -- issued a statement on Tuesday saying his office had also suffered an "error".

He claimed the motion "was interpreted in my office as a motion opposing racism", rather than anyone noticing the racist connotations and history of the phrase.